Small annoyances that add up
Individually trivial, collectively a papercut collection:
Sort resets when I change tabs. Watchlist order doesn't stick. Long names truncate with no tooltip. Search wants capitals.
None of these would make me stop using it. All of them happen every single session, and the cumulative effect is a sense that the software and I are slightly out of step all day.
The good news is they're all cheap to fix, which is a rare combination — high annoyance, low cost!